Analysis Types | ||
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Following solution types are allowed with MSC Nastran®:
SOL 101, 103, 106, 108, 111, 114 and 115.
Contact definitions in 101 (BCONTACT) are also allowed.
Allowed Analysis Types for Sensitivity-Based Optimizations
In MSC Nastran® the responses from the two following analysis types are allowed:
- SOL 101
- SOL 103
SOL 101 and SOL 103 represent the linear static and linear eigenvalue analysis, respectively. Therefore, one has to define a finite element file (e.g. bdf) containing the SOL 101 and another finite element file (e.g. bdf) containing the SOL 103 when both the responses from the static and frequency analysis are applied in the optimization formulation (e.g. minimizing the compliance but still ensuring that the first eigenfrequency is higher than a given value).
However, a workaround exists for reducing the finite element analysis CPU-time for MSC Nastran® when having responses consisting of both static and modal responses. Only the SOL 103 solution can be used when both the responses from the static and frequency analysis are applied in the optimization formulation. This is done by adding static load case in the SOL 103 solution.
| Important:
The eigenfrequency solutions of the structure are not allowed to be prestressed (then convergence is not guaranteed). Thus, the user should define a dummy load case which has no stresses and this dummy load case is referenced in the eigenfrequency analysis. |
An example of combining several frequency analyses and several static analyses in SOL 103 is given the following example:
SOL 103 ... SUBCASE 1 $ dynamic loadcase 1 METHOD=.... SPC = .... $ the structure is prestressed. $ The REFEERED subcase (20) has no stresses ! STATSUB = 20 SUBCASE 2 $ dynamic loadcase 2 METHOD=.... SPC = ..... $ the structure is prestressed. $ The REFEERED subcase (20) has no stresses ! STATSUB = 20 ....... SUBCASE 13 $ Static loadcase 1 SPC = .... LOAD = .... SUBCASE 14 $ Static loadcase 2 SPC = ... LOAD = ... ………….. SUBCASE 20 $ DUMMY static loadcase, which is stress free ! $ The command load should NOT be present here ! $ Boundary conditions are added for ensuring $ no singularities of the global stiffness and mass matrix SPC = 3 BEGIN BULK …….. ENDDATA
Important:
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Temperature Loading
TEMPERATURE(LOAD) or TEMPERATURE(BOTH) in sub cases referring the following types are supported for temperature loading using SIMULIA Tosca Structure:
- TEMP
- TEMPD
- TEMPP1
- TEMPRB
- TEMPAX
Important:
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